Re: [R] Alternate ways of finding number of occurrence of an element in a vector.

Answering my own question: if I explicitly garbage collecte before the benchmark then 'index' always wins, which probably also answers the original question. v-rep(1:1000,1:1000); x-5; gc(); benchmark(replications=200, columns=c(test,elapsed), order=elapsed, which=length(which(x==v)),

Re: [R] Alternate ways of finding number of occurrence of an element in a vector.

If one puts the gc() call prior to the expressions themselves, one gets consistently ... different results: library(rbenchmark) v-rep(1:500,1:500); x-5; benchmark( which= c(gc(),length(which(x==v))), index= c(gc(), length(v[v==x])), sum= c(gc(), sum(v==x)), replications=200,

[R] Alternate ways of finding number of occurrence of an element in a vector.

Hi, I have a vector v and would like to find the number of occurrence of element x in the same. Is there a way other than, sum(as.integer(v==x)) or length(which(x==v)) to do the this. I have a huge file to process and do this. Both the above described methods are pretty slow

Re: [R] Alternate ways of finding number of occurrence of an element in a vector.

When trying out a couple of different approaches to this problem I get rather different answers between runs. Anybody know why? library(rbenchmark) v-rep(1:1000,1:1000); x-5; benchmark(replications=200, columns=c(test,elapsed), order=elapsed, which=length(which(x==v)),